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Absolute requirements

The above coefficients are not absolutely required because they can be estimated from other characteristics. [Pg.87]

The quats are an extremely important group in medical and sanitary appHcations, with comparatively lirnited industrial appHcations. Activity against bacteria of pubHc health importance is absolutely required, with a lesser demand being made for antibingal activity. [Pg.94]

Specialized training is an absolute requirement for technical service personnel. A typical example is a person involved in supporting a polymer for which the use is the manufacture of rotationaHy molded consumer products. The technical service person is expected to be reasonably familiar with topics such as polymer rheology evaluations, gel-permeation chromatography, rotational mol ding, color science, regulatory requirements for use, mechanical and photochemical behavior of the pigmented polymer, optics, and so forth. Expertise of this variety caimot be expected to be obtained without careful... [Pg.379]

Copyright Notice. In the past, the law contained an absolute requirement that each copy of a pubHshed work bear a proper copyright notice. Failure to comply with the technicalities of the law s notice provisions resulted in the unintentional loss of protection for many works. [Pg.265]

For example, chloride and duoride ions, even in trace amounts (ppm), could cause the dissolution of aluminum metallization of complimentary metal oxide semiconductor (CMOS) devices. CMOS is likely to be the trend of VLSI technology and sodium chloride is a common contaminant. The protection of these devices from the effects of these mobile ions is an absolute requirement. The use of an ultrahigh purity encapsulant to encapsulate the passivated IC is the answer to some mobile ion contaminant problems. [Pg.188]

Limited Data First, plant data are limited. Unfortunately, those easiest to obtain are not necessarily the most useful. In many cases, the measurements that are absolutely required for accurate model development are unavailable. For those that are available, the sensitivity of the parameter estimate, model evaluation, and/or subsequent conclusion to a particiilar measurement may be very low. Design or control engineers seldom look at model development as the primaiy reason for placing sensors. Further, because equipment is frequently not operated in the intended region, the sensitive locations in space and time have shifted. Finally, because the cost-effectiveness of measurements can be difficult to justify, many plants are underinstru-mented. [Pg.2550]

Odor control by the addition of dilution air involves a problem associated with the breakdown of the dilution system. If a dilution fan, motor, or control system fails, the odorous material will be released to the atmosphere. If the odor is objectionable, complaints will be noted immediately. Good operation and maintenance of the dilution system becomes an absolute requirement, and redundant systems should be considered. [Pg.486]

It is good to limit the number of steam levels to the minimum absolutely required. [Pg.227]

Removal of particulates, colloidal matter, iron and organics. Multimedia, manganese, greensand, diatomaceous earth, brim, or carbon filter. Caution carbon filters not recommended unless absolutely required for the removal of color and odor (as they provide a medium for microbial growth). [Pg.161]

In the absence of explicit criteria, the seven characteristics listed below may be useful in evaluating management systems. Keep In mind that these characteristics are not absolute requirements facility management systems may vary significantly and still be capable of achieving the desired results. [Pg.78]

It is known that the presence of the 143-hydroxyl group and a sugar at the 3 position are absolute requirements for activity. A modified drug actodigin (100) demonstrates that reversal of the lactone 17 is consistent with activity. Reduction of digitoxigenin 91, the aglycone of digitoxin... [Pg.99]

To more fully exploit the key patent claim for the separate condenser, the firm avoided the use of high-pressure steam since it did not absolutely require a condenser. The patent claim for expansive use of steam without a condenser was used only as ammunition to restrict development in that field, although high-pressure steam replaced low-pressure steam during Watt s lifetime, and noncondensing systems... [Pg.1220]

Regular inspection and lubrication of the teeth is an absolute requirement when this type of clutch is used. If tooth profile damage is observed, it should be repaired before being returned to service. [Pg.1003]

The metal catalyst is not absolutely required for the aziridination reaction, and other positive nitrogen sources may also be used. After some years of optimization of the reactions of alkenes with positive nitrogen sources in the presence of bromine equivalents, Sharpless et al. reported the utility of chloramine-T in alkene aziridinations [24]. Electron-rich or electron-neutral alkenes react with the anhydrous chloramines and phenyltrimethylammonium tribromide in acetonitrile at ambient temperature, with allylic alcohols being particularly good substrates for the reaction (Schemes 4.18 and 4.19). [Pg.125]

Very often, the axes of the new coordinate system, or factor space are chosen to be mutually orthogonal, but this is not an absolute requirement. Of the above examples, the axes chosen for 3 and S are generally not mutually orthogonal. [Pg.80]

Deletion of the Cavl.l and Cav1.2 gene is not compatible with viable mouse pups [4, 5], The Cav1.2 channel is absolutely required for the contraction of the developing mouse heart after embryonal day 14. [Pg.1304]

The discharge pressure for the large reactor, (Pout)2 may be set arbitrarily. Normal practice is to use the same discharge pressure as for the small reactor, but this is not an absolute requirement. The length of the large reactor, L2, is chosen to satisfy the inventory constraint of Equation (3.32), and the inlet pressure of the large reactor becomes a dependent variable. The computation procedure actually calculates it first. Substitute Equation (3.23) for p (for turbulent flow) into Equation (3.32) to give... [Pg.103]

Cells exposed to excessive levels of salinity have to acquire essential nutrients from a milieu with a preponderance of ions that are potentially toxic and non-essential. In this ionic environment the success of a plant cell will require intracellular tolerance and/or specific acquisition of nutrients essential for normal metabolic functioning. The cell is also exposed to an unfavourable water balance with an absolute requirement to maintain an internal osmotic regulation that favours uptake of water into the cell (Stavarek Rains, 1984 ). [Pg.186]

Metal-assisted enantioselective catalytic reactions are one of the most important areas in organic chemistry [1-3]. They require the appropriate design and the preparation of chiral transition metal complexes, a field also of major importance in modern synthetic chemistry. These complexes are selected on both their ability to catalyze a given reaction and their potential as asymmetric inducers. To fulfill the first function, it is absolutely required that the catalysts display accessible metal coordination sites where reactants can bind since activation would result from a direct interaction between the metal ion... [Pg.271]

Digestion of PGA by the PelL enzyme yielded a mixture of unsaturated ohgogalacturonides, giving evidence that PelL is an endo-deaving lyase (17). An exo-enz3mie, such as the EC 16 PelX, would generate a single product (15). The PelL protein differs from the major E. chrysanthemi pectate lyases in its ability to cleave both PGA and methylated pectin (17). The PelL activity has a basic optimum pH and an absolute requirement for Ca + ions. Analysis of culture supernatants demonstrated that PelL is an extracellular enzyme, such as the other secondary pectate lyases (17). [Pg.316]

The r2 isolate of Fusarium oxysporum f. sp. radicis-lycopersici (FORL) produced several pectic enzymes that differ in substrate preference, reaction mechanism, and action pattern. We have detected three forms that have lyase activity, an absolute requirement for calcium, and pis of 9.20, 9.00 and 8.65. The two most alkaline forms had a weak preference for pectin whereas the other was more active on pectate. The three lyases were produced when the fungus grew on pectin and on restricted galacturonic acid (data presented in the "XV Congreso Nacional de Microbiologia" [21] and sent for publication). [Pg.748]

The enzyme had a requirement for calcium. The addition of EDTA to the reaction mixtures, resulted in complete loss of activity, whereas the addition of CaCl2 increased the activity (figure 8). Presumably, sufficient contaminating calcium ions were present in the dialyzed enzyme and substrate mixture to permit the limited activity of the controls, but apparently these were removed by chelation with EDTA. The optimum concentration was in the range of 5 to 15 M, and higher concentration resulted in a decrease in activity. Phoma medicaginis var. pinodella synthesizes a pectin lyase that lacked an absolute requirement for calcium ions but maximum enzyme activity required the presence of 1 mM Ca [25]. The lyase from Fusarium solani f sp. phaseoli, that is active on pectin and pectic acid, is calcium-dependent [30]. Most of the pectate lyases characterized are calcium-dependent the pectate lyase from Rhizoctonia solani [34] and the endopectate lyase fi om Fusarium solani f sp. pisi [31]. [Pg.758]


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Required to Obtain Absolute Values of Reduced Intensity from Experimental Readings

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